Drawing instrument



Sept'. 25 ,1923.

1,469,l92 L. SH EPARDy DRAWING INSTRUMENT Filed June 1'?. 1921 r c A65/wref fully understood from the following descrip-l Patented Sept. Z5, 1923.

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LYMAN SHEPARD, or NORFOLK, VIRGINIA., assiettes Yor ONE-HALF "roiGEORGE I..

' saluti, or NEW never, NEW JERSEY. Y

Application filed Junc- 17, 1921. Serial No. 478,387.

T0 all coito/m, t may concer-n Be it known that 1, LYMAN Sinin-inn, a citizen of theUnited States, residing at Norfolk, in the county of Noi-tolk andftate of Virginia, have invented new and useful niproveinents in Drawing Instruments, of which the following is a speciication.

ifs/ly present invention pertainsto drawing instruments and it contemplates the provision of a combination protractor, square s cale and section line spacer, through the medium of which a drattsmaii or architect may readily andeasily produce section lining and angles with but a slight'amount of efl'ort on'I his part.

' The invention also contemplates the prof vision of means whereby angles or curves such as are present in use may be Vsubstituted for the T-squareherewith shown 'and when such instruments are substituted the hatching or sectionlining be drawn in uniform manner. l Y

The invention in all ot itsdetails will be tion andclaims when the same are read in connection with the drawings accompanying and forming part of this speciticationin Figure 1 is a top plan'` view ot my novel drawing instrument and showing a T-square properly positioned thereon.

Figure 2 is a longitudinal sectional view of Figure 1. I'

Figure 3 is a transverse section of Figure 1 and showing thevworking mechanism ot my device. f

Figure l is a view partly inside elevation and partly in longitudinal section showing the spacer key 16 and' its appurtenances tory moving the drawing instrument with Ure# spe'ct to the drawing paper. y

Similar numerals ot1 reference Vdesignate,

corresponding parts in all the views yor' the drawings. Y

My novel device comprises a circular disk 1 that is secured in a removablemanner to a' drawing board above the pape'rkgr the like,

by means or the thumb tacks 2V having the,

thereof whereby the disk 3 may be rotatec independently with respect to the disk i.

At this point, 1 would distinctlyhave 'it un derstood that 1 do not 'wish to be coniined' tol any particular shape o1 disks vas the same may be square in the discretion oi' those us-Y ing the device and the degree markings do not have to agree with those shownv lon the drawings. Y Y Y vPermanently -secured with respect tothe disk 3 is aguide-way' member rhaving a Y longitudinal groove therein and on the opposite side, with respect to said member are adjustable clamps 7 each having a groove on vits innerV face similar to the groovfe of the member 5. It will be noted that 'I provide the wing-nuts 8 for the purpose of adjusting clamps 7 *withY respect to the disk 3. Adapted to beset under the clamp isanQ auxiliary scale 6 graduated as shown by 221 and said scale remains stationary 'withre' spect to the clamps-7 and disk 3 at all times;

' Adapted to be engaged vby the meinloferfl o y and Arest vunder auxiliary scale 6 is vthe* bodymeinber 9 or' a T-square that is graduated on onel of its faces asindicated and illustrated Il by 21and the said body member y.941sV provided with the groove 10 whereby casual Jdise placement of the T-square from' the member 5 and auxiliary scale 6 is precluded` The construction ofthe body member 9as set forth, is such however, as to permit 'lateral movementwith respect. to member-5 and scale 6. Manifestly, the member is'provided with the head 11 and forobvious re'a sons the member V9 has a sight' opening 12 in its longitudinal centerinv order: to enable the draftsman to properly positiony thedevice as a whole on the paper or linenl and theV said sight opening 12 may `be. covered with Aa transparent material 'when the occasion def inands.-A 'A Arranged parallel tothe sight opening and at one side of the body member 9 of .the T-square is a rack13 and secured tothe disk. 3 by means ot a bracket 17 is a casing 15 that houses the teeth, of aspacer-key 16' having the teeth. 14 that mesh withandmove the body member from right to lett-on the disk 3. 1n order to operate the teeth 14e so as to actuate the rackl 13 1 providea key 16. rhis spacerkey 16 is provided with the n tegral teeth arranged on itslower end and as' before stated thesefteeth '14 mesh with the teeth ,of therack 13 andby moving .the 'key to the right` or downwardly the teeth 14jliorce the T-square t0 thele'ft and by moving the to the4 spacer atE and abuts at its lower end key to the left the teeth force the T-square to the right. The instrument spacing device comprising a dog A, pivoted to key 16 at the point indicated and said key, is adapted to engage successfully the teethlt. The key is springbacked and the spring C is secured against stop B. The key travels in a slot formed in casing D that limits upward movement of the key. Depression of key 16 moves dog Athat rotates teeth lei and said teeth imp art motion to rack 18 on the drawing in strument.

After the key is released it will return to its normal position through action oic spring C. A i

In the practical use of the device, the same is positioned on a drawing board' by means of the thumb tacks 2 and the T-square'or otherl properly constructed angle, 4curve or drawing instrument is Jforced under the member 5 and auxiliary scale 6, it being understood that the auxiliary scale had previously been positioned under the clamps 7 The key 16 is held perpendicular so as to prevent the' teeth 14C from engaging the rack V v lir'until the vbody member 9 of the T-square arrives at the position where Zero of the scale on the body member registers with zero on the,y auxiliary scale. l/Vhen it is desired to produce section lining on the drawing the key 16 is moved downwardlyv which downward movement will cause the T-square 13o travel from left to right. The draftsman will thus be enabled to drawl section lines by bearing his straight Y line pen against the head 11' of the 'if-square. If it is desired to use the device as' a protract'or and produce angular lines either singularly or in plurality itis simply necessary to swing'the instrument on the axis '4; at any angle with respect to the disk 1. Manifestly the T- square may be positioned at any angle on the disk and at the variousdegrees indicated.

It will be gathered from the foregoing that my novel device has any number of possibilities for the purpose of producing various angles and curves as used in the drawing art'. Itrwill also be seen that at any time the distance `between the section lines maybe increased or decreased Vandin view' of the auxiliary scale construction which is adapted to be moved by a VVsimple manipulation of the screws 8, the fdraitsman may quickly and easily produce various lines.r

I have endeavored to point out the practical advantages'and construction of my device but lI would distinctly have it understood that I do not care to limit myself to the arrangement of parts as such changes in tlie'graduation of the scale of. both the auxilappended claims.

The `device is simple in construction and operation and hence a novice may with a very small amount of experience become proficient in the operation` thereof and because of its simplicity 'and small number of parts its initial cost of production, and its subsequent maintenance cost will be immaterial.

The device moreover is adapted for use as a parallel rule.

Having described my invention, vwhat I claim and desire to secure by Letters-Patent is z tion of a disk having a scale on its outer edge, means for securingthe disk in removable manner to a drawing board or the like, a second disk superimposed on the first named disk and adapted to be rotated independ ently with respect to the first named disk,V

on one' face thereof'and a rack bar arrangedl on the T-square adjacent lthe sight opening;v

the teeth of which rack bar are adapted to be 1. In a drawing instrument the combina-AY Y engaged by the pinion,H and longitudinal flanges formed on the T-square and adapted to slide under the member beneath the cas'- ing and the auxiliary scale to prevent casual displacement of'r the ll'square from 'l the last named disk. V y 2. In a device for thepurpose set forth, the combination of a plate, a secondV plate superimposed thereon and movable withl respect thereto, apinion secured onthe second Y named plate, an auxiliary scale adapted to be retained on the k'second named plate, Ia guide-way formed' on the second named plate, an instrument adapted tobe' retained on the second namedplate by thegu'i'deway and scale and a rack adapted to cooperate with the pinion.

In a device for the purpose set gforth, the combination of a stationary member, a rotatable member, secured to the stationary member, a member arrangedy on tliesuper-Y imposed member,v teeth arranged in said member andan instrument having a vrack providedV thereon for engaging the teethV of the member.v Y j 4t. In a drawing instrument, the combination of a disk,'a second disk arranged thereon and adapted to rotate on kthe first named disk, keepers secured -to the second disk, a bracket secured to the said second disk, a casing formedv in the bracket, a pinion arranged inthe casing and a key for actuating the pinion andmeans for movingV the inion an auxiliar scalearranved under] the clamps and having a channel in one edge thereof, a member secured to the plate and 15 having a channel in one edge thereof, a member comprising a casing secured to the plate, a pinion arranged in the member, a key for actuating the pinion and a member having Channels in its outer edge and adapted to be movably retained on the plate and a rack formed on the member and adapted toengage the teeth of the pinion, substantially as and for the purpose set forth. Y

In testimony whereof I have hereunto set my hand in presence 0f two subscribing wit- LYMAN SHEPARD.

` nesses.

Witnesses:

MINNIE SMERSKY, A. H. FOREMAN. 

